1. Field of the Invention
The invention relates to printer control apparatus and method which can monitor a status of a printer which receives data from a host computer or a word processor and prints.
2. Related Background Art
Hitherto, when a document from a host computer is being printed by a printer, the operation to temporarily halt the printing in the halfway or to resume the printing after an error was eliminated is executed by a panel operation on the printer side. Particularly, in the printer of the ink jet type, a cleaning of a print head is instructed by the panel operation during the printing operation. However, since the operator always works for a host computer, it is inconvenient to operate the operation panel of the printer.
In the case where the printer causes an abnormality or generate alarm information, such information is displayed by an LED or LCD display attached to the same operation panel. However, since the operator always works for the host computer, it is inconvenient to pay attention to the display on the operation panel of the printer.
In the case where a printer command including print data is sent from the host computer to the printer and is printed, the printer first receives the reception data into an input buffer and sequentially extracts the data and processes. Upon processing, further, the data is developed to an image into a drawing memory or a printing buffer and, after that, the printing is started. When those processes are seen from the host computer side, after the print data was sent, the data is printed with the elapse of a certain time. Such a time cannot be known by the host computer. Therefore, according to the conventional technique, which page the printer is printing now cannot be known from the host computer side.
In recent years, there are many systems such that in case of printing from the host computer, even if the printer is printing, in order to enable the work of the next computer to be executed, the transmission of the print data is executed by a spooler program. In such a system, when the print data is sent to the printer, the total number of print pages has already been known. Therefore, if the apparatus has means for knowing which page the printer is at present printing, the host computer can notify the operator of information indicative of the number of residual print pages. The operator can judge a remaining time which will be required to finish the printing operation, a necessity to supplement the sheets, or the like.
In the case where the printing is interrupted during the printing due to some causes such as sheet jamming of the printer or the like, the operator also cannot know which page is being printed, so that the host computer cannot judge from which page the printing should be resumed. Therefore, so far, there is an inconvenience such that the operator has to execute new jobs such that a print job in which a jam occurred is once finished and the number of jammed page is counted and the pages after the jammed page are printed.